Components of other amortizable intangible assets (Detail) (USD $) In Thousands, unless otherwise specified				9 Months Ended
	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2010	Sep. 30, 2011 Noncompete Agreements Amortizable Intangible Assets Year	Sep. 30, 2011 Customer Relationships Amortizable Intangible Assets Year	Sep. 30, 2011 Developed Technology Rights Amortizable Intangible Assets Year	Sep. 30, 2010 Developed Technology Rights Amortizable Intangible Assets Year	Sep. 30, 2011 Brands Non Amortizable Intangible Assets	Sep. 30, 2011 Amortizable Intangible Assets
Finite-Lived Intangible Assets [Line Items]
Estimated Life (Years)				5	7	7	7
Gross Carrying Amount	$ 25,410		$ 1,211	$ 240	$ 3,740	$ 4,700	$ 1,211	$ 16,730	$ 8,680
Accumulated Amortization	(795)		(115)	(12)	(151)	(632)	(115)		(795)
Net	$ 24,615	$ 2,959	$ 1,096	$ 228	$ 3,589	$ 4,068	$ 1,096	$ 16,730	$ 7,885